1. Field of the Invention
The present invention relates to digital data circuits in general, and in particular to methods and circuits for the recovery and generation of data pulses of an incoming digital data stream. More particularly still, it relates to a method and circuit for deciding that an incoming pulse is a valid data pulse or that it is not; and if it is valid, a valid pulse signal (VPS) is produced. More particularly yet, the recovered system clock is combined with the VPS to provide regenerated data pulses. Where required for bipolar data pulses, a polarity sensor is provided prior to data regeneration.
2. Prior Art of the Invention
Conventionally an edge of the recovered system clock (RCLK) was used to clock the output of a comparator (or comparators in the case of bipolar P&NDATA) into a flip-flop (F-F). This required that the recovered clock edge be centered precisely on the data pulses for optimum data recovery when the data stream is degraded by noise, interference and/or jitter.